/**
 * © 2025–2026 Skilltosky. All rights reserved.
 * Unauthorised copying, modification, or distribution is strictly prohibited.
 * PDFStudio - Main Stylesheet
 * Modern, responsive design with dark/light mode support.
 */

/* ============================================
   CSS VARIABLES (THEME SYSTEM)
   ============================================ */

:root {
    --color-primary: #11A2D7;
    --color-primary-dark: #0d8ab6;
    --color-primary-light: #4dbde3;
    --color-primary-50: #e7f6fc;

    --color-secondary: #E775A6;
    --color-secondary-dark: #cf5c90;

    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-error: #ef4444;

    /* Light mode neutrals */
    --color-bg: #ffffff;
    --color-bg-secondary: #f9fafb;
    --color-bg-tertiary: #f3f4f6;
    --color-bg-elevated: #ffffff;

    --color-text: #111827;
    --color-text-secondary: #6b7280;
    --color-text-tertiary: #9ca3af;
    --color-text-inverse: #ffffff;

    --color-border: #e5e7eb;
    --color-border-light: #f3f4f6;
    --color-border-dark: #d1d5db;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0,0,0,.05);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,.1), 0 2px 4px -1px rgba(0,0,0,.06);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,.1), 0 4px 6px -2px rgba(0,0,0,.05);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,.1), 0 10px 10px -5px rgba(0,0,0,.04);

    /* Spacing */
    --space-1: 0.25rem;  --space-2: 0.5rem;   --space-3: 0.75rem;
    --space-4: 1rem;     --space-5: 1.25rem;  --space-6: 1.5rem;
    --space-8: 2rem;     --space-10: 2.5rem;  --space-12: 3rem;
    --space-16: 4rem;    --space-20: 5rem;

    /* Border radii */
    --radius-sm: 0.25rem;  --radius-md: 0.375rem; --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;  --radius-2xl: 1rem;    --radius-full: 9999px;

    /* Typography */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', Monaco, Consolas, monospace;

    --text-xs: 0.75rem;   --text-sm: 0.875rem;  --text-base: 1rem;
    --text-lg: 1.125rem;  --text-xl: 1.25rem;   --text-2xl: 1.5rem;
    --text-3xl: 1.875rem; --text-4xl: 2.25rem;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;

    /* Z-index */
    --z-dropdown: 100; --z-sticky: 200; --z-modal: 300;
    --z-popover: 400;  --z-tooltip: 500; --z-toast: 600;

    /* Header height */
    --header-h: 64px;
}

/* Dark Mode */
[data-theme="dark"] {
    --color-bg: #0f172a;
    --color-bg-secondary: #1e293b;
    --color-primary-50: rgba(17,162,215,.15);
    --color-bg-tertiary: #334155;
    --color-bg-elevated: #1e293b;

    --color-text: #f8fafc;
    --color-text-secondary: #94a3b8;
    --color-text-tertiary: #64748b;
    --color-text-inverse: #0f172a;

    --color-border: #334155;
    --color-border-light: #1e293b;
    --color-border-dark: #475569;

    --shadow-sm: 0 1px 2px 0 rgba(0,0,0,.3);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,.4), 0 2px 4px -1px rgba(0,0,0,.2);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,.4), 0 4px 6px -2px rgba(0,0,0,.2);
}

/* ============================================
   BASE
   ============================================ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    min-height: 100vh;
    transition: background-color var(--transition-base), color var(--transition-base);
}

::selection { background-color: var(--color-primary); color: var(--color-text-inverse); }

:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; }

::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--color-bg-tertiary); }
::-webkit-scrollbar-thumb { background: var(--color-border-dark); border-radius: var(--radius-full); }
::-webkit-scrollbar-thumb:hover { background: var(--color-text-tertiary); }

/* ============================================
   TYPOGRAPHY
   ============================================ */

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-text);
}
h1 { font-size: var(--text-4xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }
h5 { font-size: var(--text-lg); }
h6 { font-size: var(--text-base); }

p { margin-bottom: var(--space-4); }

a { color: var(--color-primary); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: var(--color-primary-dark); }

/* ============================================
   LAYOUT
   ============================================ */

.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-6);
}

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }

.grid { display: grid; }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 768px) {
    .grid-cols-3 { grid-template-columns: 1fr; }
    .grid-cols-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 480px) {
    .grid-cols-2 { grid-template-columns: 1fr; }
    .grid-cols-4 { grid-template-columns: 1fr; }
}

/* ============================================
   BUTTONS
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    font-size: var(--text-base);
    font-weight: 500;
    line-height: 1.5;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
    white-space: nowrap;
}
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-primary { background-color: var(--color-primary); color: white; }
.btn-primary:hover:not(:disabled) {
    background-color: var(--color-primary-dark);
    color: white;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background-color: var(--color-bg-tertiary);
    color: var(--color-text);
    border: 1px solid var(--color-border);
}
.btn-secondary:hover:not(:disabled) {
    background-color: var(--color-bg-secondary);
    border-color: var(--color-border-dark);
    color: var(--color-text);
}

.btn-success { background-color: var(--color-success); color: white; }
.btn-success:hover:not(:disabled) { filter: brightness(1.1); transform: translateY(-1px); }

.btn-danger { background-color: var(--color-error); color: white; }
.btn-ghost { background-color: transparent; color: var(--color-text-secondary); }
.btn-ghost:hover:not(:disabled) { background-color: var(--color-bg-tertiary); color: var(--color-text); }

.btn-sm { padding: var(--space-2) var(--space-4); font-size: var(--text-sm); }
.btn-lg { padding: var(--space-4) var(--space-8); font-size: var(--text-lg); }
.btn-icon {
    width: 40px; height: 40px;
    padding: 0;
    border-radius: var(--radius-md);
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text-secondary);
}
.btn-icon:hover { background: var(--color-bg-tertiary); color: var(--color-text); }

/* ============================================
   CARDS
   ============================================ */

.card {
    background-color: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    transition: box-shadow var(--transition-fast);
}

.file-info-row {
    display: flex;
    justify-content: space-between;
    padding: var(--space-3) 0;
    border-bottom: 1px solid var(--color-border);
}
.file-info-row:last-child { border-bottom: none; }
.file-info-label { color: var(--color-text-secondary); }
.file-info-value { font-weight: 500; }

/* ============================================
   FORMS
   ============================================ */

.form-group { margin-bottom: var(--space-4); }
.form-label {
    display: block;
    margin-bottom: var(--space-2);
    font-size: var(--text-sm);
    font-weight: 500;
}
.form-input, .form-select, .form-textarea {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    font-size: var(--text-base);
    color: var(--color-text);
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.form-input:focus, .form-select:focus, .form-textarea:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-50);
    outline: none;
}
.form-input::placeholder { color: var(--color-text-tertiary); }

/* ============================================
   UPLOAD ZONE
   ============================================ */

.upload-zone {
    position: relative;
    padding: var(--space-12) var(--space-8);
    border: 2px dashed var(--color-border-dark);
    border-radius: var(--radius-2xl);
    background-color: var(--color-bg-secondary);
    text-align: center;
    transition: all var(--transition-fast);
    cursor: pointer;
}
.upload-zone:hover, .upload-zone.drag-over {
    border-color: var(--color-primary);
    background-color: var(--color-primary-50);
}
.upload-zone-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--space-4);
    color: var(--color-primary);
}
.upload-zone-text { font-size: var(--text-lg); font-weight: 500; color: var(--color-text); margin-bottom: var(--space-2); }
.upload-zone-hint { font-size: var(--text-sm); color: var(--color-text-secondary); }

/* Prevent child elements from triggering dragleave */
.upload-zone * { pointer-events: none; }
.upload-zone input { pointer-events: auto; }

/* ============================================
   PROGRESS BAR
   ============================================ */

.progress {
    width: 100%;
    height: 8px;
    background-color: var(--color-bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
}
.progress-bar {
    height: 100%;
    background: var(--color-primary);
    border-radius: var(--radius-full);
    transition: width var(--transition-base);
}

/* ============================================
   ALERTS (inline)
   ============================================ */

.alert {
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-4);
}
.alert-info    { background: rgba(59,130,246,.1); border: 1px solid rgba(59,130,246,.2); color: #1e40af; }
.alert-success { background: rgba(16,185,129,.1); border: 1px solid rgba(16,185,129,.2); color: #065f46; }
.alert-warning { background: rgba(245,158,11,.1);  border: 1px solid rgba(245,158,11,.2);  color: #92400e; }
.alert-error   { background: rgba(239,68,68,.1);   border: 1px solid rgba(239,68,68,.2);   color: #991b1b; }

[data-theme="dark"] .alert-info    { color: #93c5fd; }
[data-theme="dark"] .alert-success { color: #6ee7b7; }
[data-theme="dark"] .alert-warning { color: #fcd34d; }
[data-theme="dark"] .alert-error   { color: #fca5a5; }

/* ============================================
   TOAST NOTIFICATIONS
   ============================================ */

.toast-container {
    position: fixed;
    top: calc(var(--header-h) + var(--space-4));
    right: var(--space-4);
    z-index: var(--z-toast);
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    pointer-events: none;
    max-width: 360px;
    width: calc(100vw - var(--space-8));
}

.toast {
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    padding: var(--space-4);
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    pointer-events: auto;
    animation: toast-in var(--transition-base) forwards;
    border-left: 4px solid var(--color-primary);
}
.toast.toast-success { border-left-color: var(--color-success); }
.toast.toast-error   { border-left-color: var(--color-error); }
.toast.toast-warning { border-left-color: var(--color-warning); }

.toast-icon { flex-shrink: 0; margin-top: 1px; }
.toast-body { flex: 1; font-size: var(--text-sm); line-height: 1.5; }
.toast-title { font-weight: 600; color: var(--color-text); margin-bottom: 2px; }
.toast-msg   { color: var(--color-text-secondary); }
.toast-close {
    flex-shrink: 0;
    width: 24px; height: 24px;
    display: flex; align-items: center; justify-content: center;
    background: transparent; border: none; cursor: pointer;
    color: var(--color-text-tertiary);
    border-radius: var(--radius-sm);
}
.toast-close:hover { color: var(--color-text); background: var(--color-bg-tertiary); }

.toast.toast-out { animation: toast-out var(--transition-base) forwards; }

@keyframes toast-in {
    from { transform: translateX(calc(100% + var(--space-4))); opacity: 0; }
    to   { transform: translateX(0); opacity: 1; }
}
@keyframes toast-out {
    from { transform: translateX(0); opacity: 1; }
    to   { transform: translateX(calc(100% + var(--space-4))); opacity: 0; }
}

/* ============================================
   TOOL CARDS GRID
   ============================================ */

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: var(--space-5);
}

.tool-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: var(--space-8) var(--space-6);
    background-color: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    transition: all var(--transition-fast);
    text-decoration: none;
    color: var(--color-text);
    position: relative;
    overflow: hidden;
}
.tool-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--color-primary-50);
    opacity: 0;
    transition: opacity var(--transition-fast);
}
.tool-card:hover {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-3px);
    color: var(--color-text);
}
.tool-card:hover::before { opacity: 1; }

.tool-card-icon {
    position: relative;
    width: 60px; height: 60px;
    margin-bottom: var(--space-4);
    padding: var(--space-3);
    background: var(--color-primary);
    border-radius: var(--radius-xl);
    color: white;
    transition: transform var(--transition-fast);
}
.tool-card:hover .tool-card-icon { transform: scale(1.1); }

.tool-card-title {
    font-size: var(--text-lg);
    font-weight: 600;
    margin-bottom: var(--space-2);
    position: relative;
}
.tool-card-desc {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    position: relative;
}

/* Per-tool accent colours */
.tool-card[data-tool="edit"]    .tool-card-icon { background: #3b82f6; }
.tool-card[data-tool="sign"]    .tool-card-icon { background: #8b5cf6; }
.tool-card[data-tool="merge"]   .tool-card-icon { background: var(--color-primary); }
.tool-card[data-tool="split"]   .tool-card-icon { background: #f59e0b; }
.tool-card[data-tool="compress"].tool-card-icon { background: #10b981; }
.tool-card[data-tool="rotate"]  .tool-card-icon { background: #6366f1; }
.tool-card[data-tool="img2pdf"] .tool-card-icon { background: #ec4899; }
.tool-card[data-tool="delete"]  .tool-card-icon { background: #ef4444; }

.tool-card[data-tool="edit"]:hover    { border-color: #3b82f6; }
.tool-card[data-tool="edit"]::before  { background: rgba(59,130,246,.05); }
.tool-card[data-tool="sign"]:hover    { border-color: #8b5cf6; }
.tool-card[data-tool="sign"]::before  { background: rgba(139,92,246,.05); }
.tool-card[data-tool="split"]:hover   { border-color: #f59e0b; }
.tool-card[data-tool="split"]::before { background: rgba(245,158,11,.05); }
.tool-card[data-tool="compress"]:hover   { border-color: #10b981; }
.tool-card[data-tool="compress"]::before { background: rgba(16,185,129,.05); }
.tool-card[data-tool="rotate"]:hover   { border-color: #6366f1; }
.tool-card[data-tool="rotate"]::before { background: rgba(99,102,241,.05); }
.tool-card[data-tool="img2pdf"]:hover   { border-color: #ec4899; }
.tool-card[data-tool="img2pdf"]::before { background: rgba(236,72,153,.05); }
.tool-card[data-tool="delete"]:hover   { border-color: #ef4444; }
.tool-card[data-tool="delete"]::before { background: rgba(239,68,68,.05); }

/* ============================================
   HEADER & NAVIGATION
   ============================================ */

.header {
    position: sticky;
    top: 0;
    z-index: var(--z-sticky);
    background-color: rgba(255,255,255,.9);
    border-bottom: 1px solid var(--color-border);
    -webkit-backdrop-filter: blur(12px);
    backdrop-filter: blur(12px);
    height: var(--header-h);
}
[data-theme="dark"] .header { background-color: rgba(15,23,42,.9); }

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-h);
    gap: var(--space-4);
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    flex-shrink: 0;
    position: relative;        /* anchor for absolutely-positioned logo-icon */
    height: var(--header-h);   /* stretch full header height */
    min-width: 160px;          /* reserve space so nav doesn't overlap */
}
.logo-icon {
    position: absolute;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    height: 44px;              /* slightly smaller than full header height, with visual padding */
    width: auto;
    display: flex;
    align-items: center;
}
.logo-icon img {
    height: 100%;
    width: auto;
    object-fit: contain;
    display: block;
}

/* On small screens restore to a normal inline logo */
@media (max-width: 640px) {
    .logo { height: auto; min-width: 0; }
    .logo-icon { position: static; height: 36px; width: auto; transform: none; top: auto; }
    .logo-icon img { height: 36px; }
}

.nav {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    overflow-x: auto;
    scrollbar-width: none;
}
.nav { -ms-overflow-style: none; scrollbar-width: none; }
.nav::-webkit-scrollbar { display: none; }
.nav-link {
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    text-decoration: none;
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    white-space: nowrap;
}
.nav-link:hover { color: var(--color-text); background: var(--color-bg-tertiary); }
.nav-link.active { color: var(--color-primary); background: var(--color-primary-50); }

.header-actions { display: flex; align-items: center; gap: var(--space-2); flex-shrink: 0; }

/* Theme toggle */
.theme-toggle {
    width: 40px; height: 40px;
    display: flex; align-items: center; justify-content: center;
    background: var(--color-bg-tertiary);
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    color: var(--color-text);
    transition: all var(--transition-fast);
}
.theme-toggle:hover { background: var(--color-border); }
/* Show/hide sun vs moon based on current theme */
.theme-toggle .icon-sun  { display: none; }
.theme-toggle .icon-moon { display: block; }
[data-theme="dark"] .theme-toggle .icon-sun  { display: block; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

/* Mobile hamburger */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 40px; height: 40px;
    padding: 10px 8px;
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
}
.mobile-menu-btn span {
    display: block;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: all var(--transition-fast);
}
.mobile-menu-btn:hover { background: var(--color-bg-tertiary); }
.mobile-menu-btn.open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.mobile-menu-btn.open span:nth-child(2) { opacity: 0; }
.mobile-menu-btn.open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* Mobile nav drawer */
.mobile-nav-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.5);
    z-index: calc(var(--z-modal) - 1);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
}
.mobile-nav-overlay.open { opacity: 1; visibility: visible; }

.mobile-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(300px, 85vw);
    background: var(--color-bg-elevated);
    z-index: var(--z-modal);
    padding: var(--space-4);
    overflow-y: auto;
    transform: translateX(100%);
    transition: transform var(--transition-base);
    box-shadow: var(--shadow-xl);
}
.mobile-nav.open { transform: translateX(0); }

.mobile-nav-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-6);
    padding-bottom: var(--space-4);
    border-bottom: 1px solid var(--color-border);
}
.mobile-nav-title { font-weight: 700; font-size: var(--text-lg); }
.mobile-nav-close {
    width: 36px; height: 36px;
    display: flex; align-items: center; justify-content: center;
    background: transparent; border: none; cursor: pointer;
    color: var(--color-text-secondary);
    border-radius: var(--radius-md);
}
.mobile-nav-close:hover { background: var(--color-bg-tertiary); color: var(--color-text); }

.mobile-nav-link {
    display: flex;
    align-items: center;
    padding: var(--space-4);
    color: var(--color-text);
    text-decoration: none;
    border-radius: var(--radius-lg);
    font-weight: 500;
    transition: all var(--transition-fast);
    margin-bottom: var(--space-1);
}
.mobile-nav-link:hover { background: var(--color-bg-tertiary); color: var(--color-text); }
.mobile-nav-link.active { background: var(--color-primary-50); color: var(--color-primary); }

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    padding: var(--space-16) 0;
    text-align: center;
    background: linear-gradient(135deg, var(--color-bg-secondary) 0%, var(--color-primary-50) 100%);
}
[data-theme="dark"] .hero { background: linear-gradient(135deg, var(--color-bg-secondary) 0%, rgba(17,162,215,.1) 100%); }

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    background: var(--color-primary);
    color: white;
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    font-weight: 500;
    margin-bottom: var(--space-6);
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    margin-bottom: var(--space-4);
    color: var(--color-text);
    line-height: 1.1;
}
.hero-title span { color: var(--color-primary); }

.hero-subtitle {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto var(--space-8);
}

/* ============================================
   PDF EDITOR INTERFACE
   ============================================ */

.editor-container {
    display: flex;
    height: calc(100vh - var(--header-h));
    overflow: hidden;
}
.editor-sidebar {
    width: 280px;
    background-color: var(--color-bg-secondary);
    border-right: 1px solid var(--color-border);
    padding: var(--space-4);
    overflow-y: auto;
}
.editor-main { flex: 1; display: flex; flex-direction: column; overflow: hidden; }

.editor-toolbar {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-4);
    background-color: var(--color-bg-elevated);
    border-bottom: 1px solid var(--color-border);
    overflow-x: auto;
    flex-wrap: nowrap;
}
.toolbar-btn {
    display: flex; align-items: center; justify-content: center;
    width: 40px; height: 40px;
    background: transparent;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
    flex-shrink: 0;
}
.toolbar-btn:hover { background: var(--color-bg-tertiary); color: var(--color-text); }
.toolbar-btn.active { background: var(--color-primary-50); color: var(--color-primary); border-color: var(--color-primary); }
.toolbar-separator { width: 1px; height: 24px; background: var(--color-border); margin: 0 var(--space-2); flex-shrink: 0; }

.editor-canvas-container {
    flex: 1;
    overflow: auto;
    padding: var(--space-6);
    background-color: var(--color-bg-tertiary);
}
.editor-canvas { margin: 0 auto; background: white; box-shadow: var(--shadow-lg); }

/* Page Thumbnails */
.page-thumbnails { display: flex; flex-direction: column; gap: var(--space-3); }
.page-thumbnail-wrapper {
    position: relative;
    padding: var(--space-2);
    background: var(--color-bg);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}
.page-thumbnail-wrapper:hover { border-color: var(--color-primary-light); }
.page-thumbnail-wrapper.active { border-color: var(--color-primary); }
.page-thumbnail { display: block; width: 100%; }
.page-thumbnail-number {
    position: absolute;
    top: var(--space-2); left: var(--space-2);
    padding: 2px var(--space-2);
    background: rgba(0,0,0,.6);
    color: white;
    border-radius: var(--radius-sm);
    font-size: var(--text-xs);
    font-weight: 500;
}

/* ============================================
   SIGNATURE PAD
   ============================================ */

.signature-pad-container {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
}
.signature-pad {
    width: 100%;
    height: 200px;
    background: white;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    cursor: crosshair;
    touch-action: none;
}
.signature-tabs { display: flex; gap: var(--space-2); margin-bottom: var(--space-4); }
.signature-tab {
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    font-weight: 500;
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    cursor: pointer;
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
}
.signature-tab.active { background: var(--color-primary); border-color: var(--color-primary); color: white; }

/* ============================================
   MODALS
   ============================================ */

.modal-overlay {
    position: fixed; inset: 0;
    background: rgba(0,0,0,.5);
    display: flex; align-items: center; justify-content: center;
    z-index: var(--z-modal);
    opacity: 0; visibility: hidden;
    transition: all var(--transition-base);
}
.modal-overlay.active { opacity: 1; visibility: visible; }
.modal {
    background: var(--color-bg-elevated);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    max-width: 90vw;
    max-height: 90vh;
    overflow: auto;
    transform: scale(0.95);
    transition: transform var(--transition-base);
    width: 480px;
}
.modal-overlay.active .modal { transform: scale(1); }
.modal-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: var(--space-4) var(--space-6);
    border-bottom: 1px solid var(--color-border);
}
.modal-title { font-size: var(--text-lg); font-weight: 600; }
.modal-close {
    width: 32px; height: 32px;
    display: flex; align-items: center; justify-content: center;
    background: transparent; border: none; border-radius: var(--radius-md);
    cursor: pointer; color: var(--color-text-secondary);
}
.modal-close:hover { background: var(--color-bg-tertiary); color: var(--color-text); }
.modal-body { padding: var(--space-6); }
.modal-footer {
    display: flex; justify-content: flex-end; gap: var(--space-3);
    padding: var(--space-4) var(--space-6);
    border-top: 1px solid var(--color-border);
}

/* ============================================
   LOADING OVERLAY
   ============================================ */

.loading-overlay {
    position: fixed; inset: 0;
    background: rgba(255,255,255,.92);
    display: flex; flex-direction: column;
    align-items: center; justify-content: center;
    z-index: var(--z-modal);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-base), visibility var(--transition-base);
}
[data-theme="dark"] .loading-overlay { background: rgba(15,23,42,.92); }

.loading-overlay.active { opacity: 1; visibility: visible; }

.loading-content { display: flex; flex-direction: column; align-items: center; gap: var(--space-4); }
.spinner {
    width: 52px; height: 52px;
    border: 4px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.loading-text {
    font-size: var(--text-lg);
    font-weight: 500;
    color: var(--color-text-secondary);
    text-align: center;
}
.loading-progress { width: 240px; text-align: center; }
.loading-progress-label { font-size: var(--text-sm); color: var(--color-text-tertiary); margin-top: var(--space-2); }

/* ============================================
   RESULT CARD (used after processing)
   ============================================ */

.result-card {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-2xl);
    overflow: hidden;
    text-align: center;
    padding: var(--space-10) var(--space-8);
}
.result-card-icon {
    width: 72px; height: 72px;
    margin: 0 auto var(--space-4);
    background: rgba(16,185,129,.1);
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    color: var(--color-success);
}
.result-card-title { font-size: var(--text-2xl); margin-bottom: var(--space-2); }
.result-card-subtitle { color: var(--color-text-secondary); margin-bottom: var(--space-8); }
.result-stats {
    display: flex;
    justify-content: center;
    gap: var(--space-8);
    margin-bottom: var(--space-8);
    flex-wrap: wrap;
}
.result-stat { text-align: center; }
.result-stat-value { font-size: var(--text-2xl); font-weight: 700; color: var(--color-primary); }
.result-stat-label { font-size: var(--text-sm); color: var(--color-text-secondary); }
.result-actions { display: flex; justify-content: center; gap: var(--space-3); flex-wrap: wrap; }

/* ============================================
   FEATURES SECTION
   ============================================ */

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
}
.feature-item { text-align: center; }
.feature-icon {
    width: 72px; height: 72px;
    margin: 0 auto var(--space-4);
    background: var(--color-primary-50);
    border-radius: var(--radius-2xl);
    display: flex; align-items: center; justify-content: center;
    color: var(--color-primary);
    transition: transform var(--transition-fast);
}
.feature-item:hover .feature-icon { transform: translateY(-3px); }
.feature-title { font-size: var(--text-lg); font-weight: 600; margin-bottom: var(--space-2); }
.feature-desc { font-size: var(--text-sm); color: var(--color-text-secondary); }

@media (max-width: 768px) {
    .features-grid { grid-template-columns: 1fr; gap: var(--space-6); }
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    padding: var(--space-12) 0;
    background-color: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
}
.footer-content {
    display: grid;
    grid-template-columns: 1.8fr 1fr 1fr 1fr;
    gap: var(--space-8);
    margin-bottom: var(--space-8);
}
.footer-logo-link { display: inline-block; margin-bottom: var(--space-3); }
.footer-tagline {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-4);
}
.footer-trust-badges {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}
.footer-trust-badges li {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-xs);
    color: var(--color-text-secondary);
}
.footer-trust-badges svg { flex-shrink: 0; color: var(--color-primary); }
.footer-section h4 {
    font-size: var(--text-sm);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: .05em;
    margin-bottom: var(--space-4);
}
.footer-links { list-style: none; }
.footer-links li { margin-bottom: var(--space-2); font-size: var(--text-sm); color: var(--color-text-secondary); }
.footer-links a { font-size: var(--text-sm); color: var(--color-text-secondary); }
.footer-links a:hover { color: var(--color-primary); }
.footer-bottom {
    padding-top: var(--space-6);
    border-top: 1px solid var(--color-border);
    text-align: center;
    font-size: var(--text-sm);
    color: var(--color-text-tertiary);
}

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 1024px) {
    .editor-sidebar { width: 240px; }
    .nav-link { font-size: 12px; padding: 4px 6px; }
}

/* Switch to hamburger at 900px — covers iPad Air (820px) and similar tablets */
@media (max-width: 900px) {
    .nav { display: none; }
    .mobile-menu-btn { display: flex; }
    .logo { min-width: 0; }
    .logo-icon { height: 44px; }
    .logo-icon img { height: 44px; }
}

@media (max-width: 768px) {
    .container { padding: 0 var(--space-4); }

    .nav { display: none; }
    .mobile-menu-btn { display: flex; }

    .tools-grid { grid-template-columns: repeat(2, 1fr); gap: var(--space-4); }

    .editor-container { flex-direction: column; height: auto; }
    .editor-sidebar { width: 100%; max-height: 200px; border-right: none; border-bottom: 1px solid var(--color-border); }
    .page-thumbnails { flex-direction: row; overflow-x: auto; }
    .page-thumbnail-wrapper { flex-shrink: 0; width: 100px; }

    .hero { padding: var(--space-10) 0; }
    .footer-content { grid-template-columns: 1fr 1fr; }
    .footer-brand { grid-column: 1 / -1; }
    .modal { width: 90vw; }
}

@media (max-width: 480px) {
    .tools-grid { grid-template-columns: 1fr; }
    .btn-lg { width: 100%; }
    .editor-toolbar { flex-wrap: wrap; }
    .footer-content { grid-template-columns: 1fr; text-align: center; }
    .footer-trust-badges { align-items: center; }
    .footer-logo-link { display: block; text-align: center; }
    .result-stats { gap: var(--space-4); }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

.sr-only {
    position: absolute; width: 1px; height: 1px;
    padding: 0; margin: -1px; overflow: hidden;
    clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}
.text-center { text-align: center; }
.text-left   { text-align: left; }
.text-right  { text-align: right; }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold   { font-weight: 700; }
.hidden      { display: none !important; }
.invisible   { visibility: hidden; }
.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.w-full  { width: 100%; }
.h-full  { height: 100%; }
.rounded    { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }